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Harnessing non-equilibrium forces to optimize work extraction
Kristian Stølevik Olsen1, Rémi Goerlich2,3, Yael Roichman3,4
1Institut für Theoretische Physik II - Weiche Materie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany. kristian.olsen@hhu.de.
None:
While optimal control theory offers effective strategies for minimizing energetic costs in noisy microscopic systems over finite durations, a significant opportunity lies in exploiting the temporal structure of non-equilibrium forces. We demonstrate this by presenting exact analytical forms for the optimal protocol and the corresponding work for any driving force and protocol duration. We also derive a general quasistatic bound on the work, relying only on the coarse-grained, time-integrated characteristics of the applied forces. Notably, we show that the optimal protocols automatically harness information about non-equilibrium forces and an initial state measurement to extract work. These findings chart new directions for designing adaptive, energy-efficient strategies in noisy, time-dependent environments, as illustrated through our examples of periodic driving forces and active matter systems. By exploiting the temporal structure of non-equilibrium forces, this largely unexplored approach holds promise for substantial performance gains in microscopic devices operating at the nano- and microscale.
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